Numerical simulation on cladding track, fluid flow field and temperature field in laser cladding process with powder feeding

A computational model for determining the configuration and thickness of cladding layer was presented. Liquid, mushy and solid regions in laser cladding process were considered as a continuum, and the continuum model for binary solid - liquid phase change system was used to simulate the velocity and temperature fields, and a fixed - grid and moving coordinate system were adopted to deal with fluid flow and heat transfer problem involving moving heat source. The sensible enthalpy was used as a dependent variable in energy equation, and the terms including latent heat were merged into source term. Based on Lambert - Beer equation and Mie's theory, the interaction between powder stream and laser beam was treated to fulfil the situation of high powder concentration. The commercial software PHOENICS, to which several modules related with source terms, boundary conditions, interaction between powder stream and laser beam and configuration of cladding layer were appended, was used to accomplish the simulation. The results obtained by the simulation are coincident with those measured in experiment basically.